For those of you who like the whole out of the box experience, don't get too excited. The package is very unassuming, consisting of a little leaflet, a support card, a single DVD, and the ubiquitous Apple stickers. It actually felt a bit flimsy by Apple's standards, but it's not the packaging that's on trial with this upgrade.
Installation was a breeze. I started on the MacBook Pro laptop on which I intended to do an in-place installation. The installation app ran straight from the DVD with no need to reboot to the optical drive. I customised the installation and removed all the unwanted language, printer and X windows software, as the laptop only had about 33Gb space available (but more on that later). Installation took about 35 minutes before user input was required. After about 12 minutes the system rebooted itself, which caused momentary heart failure, but I guess I should have expected it. After all, a Windows installation often causes three or four reboots before it's done.
That was pretty much it for the installation - no wizardry, no fireworks, just a workmanlike approach to getting the job done as quickly and painlessly as possible.
Some statistics for those interested. Bootup time was reduced by about a minute (just under 2 minutes to have a fully functional system with all login items up and running). Shut-down time was halved to about 5 seconds.
There was an additional 9.3Gb of disk space available (using proper old fashioned Gb measures, not the new 'decimal' standard that Apple have now adopted). In the main user folder, there were about 2500 fewer items, saving about 0.2Gb of space. On my MBP this was a significant increase in available space, which I'm very grateful for. My system had already been stripped of extra language and unwanted code by running Monolingual, so other users may see even greater savings. On my Hackintosh, the extra space may prove to be even more significant. Obviously, there are knock on effects, especially with TimeMachine, as backups should get smaller and faster.
I then did the installation on the iMac with the dodgy internal disk. The disk is clearly beyond repair - although the installation programme could see it, it refused to try and do anything with it as SMART errors prevented this. Nothing really to add regarding the installation on to the external Firewire 400 drive. It took a little bit longer - about 45m, but that was only to be expected.
With the initial installation over, I had a brief opportunity to look around. First place to look was the installation created folder called Incompatible Software. To my relief this was almost empty, with only two .kext files on show, neither of which I recognised. This folder is used to remove and store software that is known to cause problems with Snow Leopard. It does not make any attempt to remove software that doesn't work under OS X 10.6 - you need to do this by trial and error and checking out web sites for your most critical applications. On the MBP, the only issues (so far) were with Surplus Meter which I use to monitor my mobile Broadband access which required Rosetta installation (I had deselected Rosetta during the installation) and PlugSuit, an application enhancer, which forced the system to request an admin password every time an application was launched. Disabling PlugSuit in it's PreferencesPane solved the problem without doing any damage.
iStat menus no longer work under Snow Leopard (already documented), which meant that the time and date no longer appeared in the menu bar. It took some searching to find where the preferences information to fix this was located, but that now works OK (look for the Clock tab under Date and Time in System Preferences). To my relief Hyperspaces, Dock Spaces and Docker all worked fine (although the Dock colour had been reset).
The main issue has been with Mail which has undergone an internal (but not external) re-write. None of my mail add-ins worked following installation (these include DockStar, Mail Iconizer, Mail Tags, LetterBox, Mail Appetiser and Mail Act-on). Some upgrades are already available, others are work in progress. Mail rebuilds it's databases the first time that it is run following installation of OS X 10.6. This in itself caused no problems, but it seems that somewhere along the line my KeyChain has been corrupted. After spending over three hours late last night I finally dumped the KeyChain and created a new default. This seems to have done the trick. Fingers crossed.
Overall I'm pleased that everything was relatively painless, that a few extra gigabytes of space have emerged, and that most of the day to day applications are functioning as normal (or slightly sprightlier). Now I've got a chance to get back to doing some real work, and I'll get a better feel for the changes and find out any other issues. I'll get you updated on my findings.
As the saying goes :
"Learn all you can from the mistakes of others. You won't have time to make them all yourself".